Hay fever guidelines don't reflect real life

NEW YORK (Reuters Health) - Fewer than one in 10 people with hay fever would be allowed to take part in the drug trials that end up dictating their treatment, French researchers have found.

That's because such gold standard studies, called randomized controlled trials, have very strict rules for participation to ensure the results are as "pure" as possible.

A person with hay fever and, say, liver problems might respond differently to a new drug than someone who is otherwise healthy. The problem is that once the drug enters the market, all kinds of patients will be getting it from their doctor.

For instance, the first allergy drug to relieve sneezing, itchy eyes and congestion without drowsiness -- an antihistamine sold as Seldane in the U.S. -- reached millions of Americans before it became clear that it caused heart problems in certain people, including those with liver disease.

The U.S. Food and Drug Administration finally decided it was too dangerous to remain on the market more than a decade after it was approved.

While this is a worst-case scenario, drugs often turn out to be less effective in real life than in precisely orchestrated clinical trials, said Dr. Jean Bousquet, of the Centre de recherche en �pid�miologie et Sant� des Populations in Villejuif, who led the new work.

Bousquet and his colleagues asked primary care physicians to interview their hay fever patients and determine whether they fulfilled the requirements to participate in the four largest trials of allergy drugs.

They ended up with 311 sniffling patients from all across the Languedoc-Roussillon region.

"We found that only 7.4 percent of the patients seen in primary care would have been included in the randomized controlled trials," said Bousquet, whose findings appear in the Journal of Allergy and Clinical Immunology.

"The problem is that guidelines are based on randomized controlled trials," he told Reuters Health, adding that his findings apply to many other areas of medicine.

In the case of hay fever, which affects tens of millions of Americans, earlier work by Bousquet's team has shown that doctors following guidelines actually have a better chance of helping their patients than if they're left to their own choice of treatment.

But it's hard to say if that goes for other diseases as well.

Dr. Mitchell H. Grayson, an allergy expert at the Medical College of Wisconsin in Milwaukee who was not involved in the study, said the new findings were concerning, though hardly surprising.

"You don't want your drug to fail because it's diluted out by people having different diseases," he said. "You need to do the randomized controlled trial first to show the therapy works."

But there is little incentive for companies to do performance tests once a drug -- proved safe and effective in a select group of patients only -- has hit the market.

"That leaves the bigger question of what happens when you go and use the drug in the real world," Grayson said, although he added that the FDA does collect reports of potential side effects. In special cases the agency might also require studies after the drug has been brought to market.

While doctors agree this system isn't ideal, the problem is that real-life studies are very costly.

"Who is going to run that study and who is going to pay for it?" said Grayson. "The pharmaceutical industry would be loath to do it, because they risk finding their drug is less efficient."

According to Bousquet, certain European countries, including France and the UK, already require studies that include a broad swath of patients for many new drugs.

"For many diseases this might be important," he said. "You need more real-life trials not excluding patients."